Different Types Of Operations Research Articles

Step forward in epidemiological modeling: Introducing the rate indicator function to capture waves

In the last centuries, mathematical models have been used to depict the dynamic evolution of infectious diseases’ spread. The aim is to determine the total numbers of infected, recovered, and susceptible individuals; however, they only represent accumulated values due to the complexities of collected data. Having the graphical representations of these classes as accumulated values, one may not directly be able to predict waves to determine a day-to-day number of newly infected cases as some additional calculations are required. Collected data from real-world situations are represented as day-to-day new infections; they help determine in addition numbers of waves. However, current existing mathematical models cannot be used for wave prediction. While knowing the predicted numbers of waves, policymakers can take adequate measures to control the situation. To solve this problem, we questioned the fact that the rates of infection and recovery are constant and suggested an indicator rate function obtained using experimental data. To see the effect of this function, we considered a simple SIR model, which was modified by introducing rate indicator functions for infected and recovered classes. To include nonlocal behaviors in the mathematical model, different types of differential operators, including classical and fractional derivatives, were used. The models were solved numerically using well-known numerical schemes. The numerical solutions were plotted for different theoretical parameters; the results depict real-world behaviors. To test the efficiency of this new approach, we collected data from South Africa and compared them with our model. Not only our model could predict waves, but also it fits experimental data very accurately. This new approach will open new doors of investigation toward a revolution in epidemiological modeling.

Optimizing the process of fire detection in warehouses considering the type and location of fire detectors

An integral condition for avoiding damage due to fires in warehouses, or at least minimizing them, is the early detection of fires using fire protection systems, as well as its timely localization. Depending on which fire detectors are selected to protect the relevant premises and where they are installed, the time of operation of all elements of automatic control systems in case of a fire will depend. The review of literary data revealed that at present there is no comprehensive approach to choosing the optimal placement in warehouses. In addition, the optimal placement of fire detectors within the room, taking into consideration the type of fire load, has not been sufficiently studied. Therefore, the purpose of the current study is to establish the dependence of the time of operation of different types of fire detectors on the type of combustible material, namely its mass burnout rate, distance, and height of placement of detectors from a potential fire site. This paper reports a procedure for conducting an experimental study to identify the appropriate dependence for warehouses. The results of the experiments showed that the most effective in warehouses are targeted fire smoke detectors and aspiration systems. Based on the results of a complete factor experiment, nonlinear empirical dependences to determine the time of operation of smoke fire detectors on the above factors were built. The resulting empirical dependences make it possible to choose fire detectors and optimally place them within a room. The average error in these dependences when compared with the experimental data is 6.9 %. The use of the derived dependences makes it possible to reduce the time of operation of fire detectors by 14 s in comparison with their placement in accordance with building codes

Derivative Operator of Order ε+ρ-1 Associated with Differential Subordination and Superordination

Professors Miller and Mocanu established the theory of differential subordination and its twin, the theory of differential super ordination, which are both based on reinterpreting fundamental inequalities for real-valued functions for the situation of complex-valued functions. Using different types of operators to study subordination and super ordination characteristics is a technique that is still extensively employed, with some investigations leading to sandwich-type theorems, as is the case in the current work. The objective of this work is to derive differential Subordination and Super ordination outcomes using the derivative operator of order E+-1. Differential subordination and super ordination results are achieved for analytic functions connected with the integral operator in the open unit disc. These findings are achieved by examining relevant types of admissible functions, differential supremacy theorem, several operator differential hyperboloids requiring partial integration of a stacking suprageometric function are produced, as well as the best subordinates. The result of a sandwich type links the outcomes of dependency and dependency using Theorem 9. Keep track of intriguing corollaries for certain occupations by using the best subordinate and dominant skills. Presented in this paper may be used to motivate the usage of alternative hyper-geometric functions related to partial integration.

Prevalence and outcome of hysterectomy in a peripheral medical college – A data-based retrospective study

Aims and Objectives: The study aimed evaluation of prevalence, demographic features, clinical presentation, indication, intra-operative findings, different types of operation, and histopathological diagnosis of patients who underwent hysterectomy in our center. Materials and Methods: This retrospective study done over 3 years from May 2017 to April 2020 in Department of Obstetrics and Gynecology of Rampurhat Government Medical College, West Bengal India. Case record and data of each patient were obtained from medical record section of the hospital and analyzed after taking permission of concerned authority. Inclusion criteria: Those underwent hysterectomy for gynecological indications during our study periods. Results: During the study period, total 6014 obstetrical and gynecological surgery performed; out of them, 424 cases of hysterectomies were studied, maximum patients (64.85 %) underwent hysterectomy at the age group of 41–50 years. Menorrhagia was the most common (61.32%) presenting complains. Leiomyoma was the most common (27.12%) indication followed by abnormal uterine bleeding (22.17%) and pelvic organ prolapses (11.57%). Maximum (79.25%) with abdominal route and 20.75% cases through vaginal approach. Total abdominal hysterectomy with bilateral salpingo-ophorecctomy 270 cases (63.69%), vaginal hysterectomy with pelvic floor repair 60 (14.15%), total abdominal hysterectomy without oophorectomy 50 (11.79%), and radical hysterectomy 16(3.77%).Dominant histopathological type was leiomyoma (22.88%). Among various post-operative complications, urinary tract infection was the most common (9.19%), the most of the postoperative complication was found in abdominal hysterectomy. Conclusion: For treating pelvic pathologies such as uterine bleeding, adenomyosis, fibroid, pelvic inflammatory disease, malignant disorder, and genital prolapse hysterectomy is preferred procedure and abdominal route was most common. Complication of vaginal hysterectomy is less than abdominal approach. Vaginal approach should be preferable approach.

A Wave Diffraction Problem with Higher Order Impedance Boundary Conditions

In this paper, we consider an impedance boundary transmission problem for the Helmholtz equation originated by a problem of wave diffraction by an infinite strip with higher order imperfect boundary conditions. Operator theoretical methods and relations between operators are built to deal with the problem and, as consequence, a transparent interpretation of the problem in an operator theory framework are associated to the problem. In particular, different types of operator relations are exhibited for different types of operators acting between Lebesgue and Sobolev spaces on a finite interval and the positive half-line. All this has consequences in the understanding of the structure of this type of problems. At the end, we describe when the operators associated with the problem enjoy the Fredholm property in terms of the initial space order parameters.

Effective ROCOF-Based Islanding Detection Technique for Different Types of Microgrid

This article presents an adaptive rate of change of frequency (ROCOF)-based passive islanding detection technique (IDT) to overcome the non-detection zone (NDZ) issue and limitation of existing IDTs. The proposed ROCOF-based passive IDT relies on the settings of the phase-locked loop (PLL) closed-loop control system for frequency, ROCOF, and threshold ROCOF value for the PCC relay-setting calculations. So, the PLL results in alternate frequency and ROCOF output value with respect to the PLL settings modification. The PLL settings can be different in different types of microgrid systems. Therefore, the proposed adaptive ROCOF-based IDT provides a generic solution for islanding detection applications for the safe and reliable operation of different types of microgrid systems. The adaptive ROCOF-based IDT is developed and implemented on two different types of the microgrid systems such as i) generator-based microgrid ii) generator, PV, and storage-based hybrid microgrid in Matlab/Simpower system. Results showed that the proposed IDT successfully detected the islanding condition even with zero power mismatch and it is fully capable to distinguish between islanding (loss of mains and external fault) and nonislanding (internal fault, load switching, motor starting, etc.) conditions with a diverse range of operating conditions.

Improving the Statistical Qualities of Pseudo Random Number Generators

Pseudo random and true random sequence generators are important components in many scientific and technical fields, playing a fundamental role in the application of the Monte Carlo methods and stochastic simulation. Unfortunately, the quality of the sequences produced by these generators are not always ideal in terms of randomness for many applications. We present a new nonlinear filter design that improves the output sequences of common pseudo random generators in terms of statistical randomness. Taking inspiration from techniques employed in symmetric ciphers, it is based on four seed-dependent substitution boxes, an evolving internal state register, and the combination of different types of operations with the aim of diffusing nonrandom patterns in the input sequence. For statistical analysis we employ a custom initial battery of tests and well-regarded comprehensive packages such as TestU01 and PractRand. Analysis results show that our proposal achieves excellent randomness characteristics and can even transform nonrandom sources (such as a simple counter generator) into perfectly usable pseudo random sequences. Furthermore, performance is excellent while storage consumption is moderate, enabling its implementation in embedded or low power computational platforms.

A novel unbalanced power flow analysis in active AC-DC distribution networks considering PWM convertors and distributed generations

Recent major achievements in power electronic technologies have expedited the development and proliferation of small-scale distributed generations (DGs). AC-DC distribution network creates a novel paradigm to attain the utmost benefits through smoothing the operation of different types of DGs. However, due to the asymmetrical electrifying of single-phase loads with different consumptions, variations in output power of the small-scale DGs connected to each phase, and disparate line parameters of the network, operation under unbalanced condition is inevitable. Therefore, performing AC-DC load flow analysis considering an unbalanced condition is indispensable to estimate the system states. In this paper, a novel direct approach based on backward-forward sweep (BFS) algorithm is proposed for power flow analysis in AC-DC distribution networks that applies Clarke’s transformation to model the operation of pulse width modulation (PWM) converters at unbalanced operation condition. Different control strategies including input power control (IPC), input output power control (IOPC), and output power control (OPC) are considered in the proposed formulation. Furthermore, to investigate the impacts of DGs on AC-DC distribution networks, an effective approach based on sensitivity matrix calculation is proposed to approximately update the outputs of DGs in each iteration. To evaluate the performance of the approach and examine its efficiency, the proposed formulations are applied to a hypothetical 123-bus AC-DC test system, containing different type of DGs and power converters, and compared with a heuristic method. The simulation results verify the effectiveness and applicability of the proposed method in load flow analysis of AC-DC distribution networks in unbalanced condition.

Different Types of Operations on Neutrosophic Graphs

The fuzzy graph theory uses a substantial and important role in modelling and structuring many optimization problems. DIfferent type of uncertainties exist in most of the optimization problems in real lIfe scenarios due to indeterminate and incomplete information and it is a challenging task for the expert to design those optimization problems applying fuzzy graph. To design the incomplete, uncertainty and vagueness in graphical optimization problems, several extensions of graph theoretical ideas are proposed. The idea of neutrosophic graph plays an important role to manage the uncertainty, linked with the indeterminate and incomplete data/information of any optimization problem. In this manuscript, we present the idea of regular neutrosophic graph, strong neutrosophic graph, bipartite neutrosophic graph, regular neutrosophic graph, and regular strong neutrosophic graph. We also introduce six different operations on neutrosophic graph, viz., cartesian product, composition, join, direct product, lexicographic and strong product.

Energy from nuclear fission

The physics of nuclear fission will be briefly illustrated, from the basic mechanism behind this phenomenon to the relevant physical quantities like nuclear cross sections, neutron flux and reaction products, together with the accompanying phenomenon of neutron capture and its role in determining how the fuel transforms in a nuclear reactor. The basic concepts underlying the operation of different types of nuclear reactors will be illustrated, along with the concept of fuel cycle. The aspects of radioactive waste, fuel resources and safety will also be briefly illustrated.

ANALYSIS OF COMPLICATIONS OF SURGICAL TREATMENT IN PATIENTS WITH LUNG TUMORS

The aim of the study was to identify factors that are associated with complications after surgery for lung cancer.
 Materials and Methods. Retrospective analysis of the surgical treatment results in patients with lung cancer who were operated on in 2010-2014 at the department of thoracic surgery of the Lviv Oncological Regional Treatment and Diagnostic Center. The study included 461 patients. The data of each patient were divided into the following groups: general characteristics, tumor characteristics, treatment characteristics, and complications. The whole cohort of patients was analyzed and their separate subgroups were compared by age, type of complications, and type of surgery.
 Results and Discussion. Elderly patients have three times higher levels of postoperative dyspnea and much higher levels of cardiac arrhythmias. Pulmonary complications are more common in men, after more aggressive surgeries with longer time of operative pulmonary ventilation; increase with age. This subgroup is also characterized by longer postoperative period and a higher in-hospital mortality rate. Postoperative complications such as dyspnea, fistula of the bronchial stump, and pleural empyema, higher levels of pleural punctures, and postoperative bed-day were more common in the group of patients who underwent pneumonectomy. A higher level of postoperative pneumonia and a longer drainage period were observed in the group of other operations. It is noteworthy that the level of dyspnea in elderly patients who underwent pneumonectomy is three times higher.
 Conclusions. There are age-related features connected to the onset of postoperative complications in patients with lung tumors who have undergone surgery. Complications typical for the patients after different types of operations were found. It is established that the age of patients and the type of surgical treatment significantly change the palette of postoperative complications. An improved method for predicting complications is required.

Global right inverses for Euler type differential operators on the space of smooth functions

We study Euler type partial differential operators P(θ) admitting a continuous linear right inverse on the space of smooth functions defined on Rd. Specifically, if the canonical unit vectors {ej|j≤d} are non characteristic for P then P(θ) admits a continuous linear right inverse iff P(∂) is hyperbolic w.r.t. ej for any j≤d.

Factors Affecting the Selection of the Bariatric Surgeon-A Survey Study

There are various factors considerd by the patients in the process of selecting the hospital and the surgeon like professional sertifications. The experience of the surgeon for all types of surggeries has a great influence on the patients' preference. In some surgical procedures patients prefer gender concordant surgeons like gynecological operations. These factors have been evaluated in many studies regarding different types of operations.

Partial vs. superficial parotidectomy for surgical treatment of pleomorphic adenoma of the parotid gland

Purpose: Superficial parotidectomy is still the gold standard in surgical therapy for pleomorphic adenoma. Recently, less extensive procedures such as extracapsular dissection and before that partial parotidectomy were introduced. We analyzed the data of patients treated with either partial or superficial parotidectomyand compared recurrence rates and postoperative morbidity.
 Methods: WA retrospective analysis of all the patients with pleomorphic adenomas who were treated at the Department of Otolaryngology from 2002 to 2016 was performed. The patients’ data were analyzed for outcome measures: facial nerve deficit, margin status, Frey’s syndrome, tumor size, duration of surgery and tumor recurrence.
 Results: During this period, 186 patients with pleomorphic adenomas of the parotid gland underwent surgery, 177 of these for the first time. Nine patients were referred to us with recurrence from another institution. Among these 177 patients, 86 were treated by partial parotidectomy, 75 by superficial parotidectomy and 16 by total parotidectomy. Transient facial weakness and the duration of surgery differed significantly between the different types of operation. Frey’s syndrome and recurrence rate were not significantly different between the groups.
 Conclusions: Radical surgery could be achieved with limited removal of the parotid while the recurrence rate was the same between the groups.

The Risk Related to the Influence of Sleep Deprivation on the Reliability of Human on the Example of Pilot

Abstract The purpose of this publication is to discuss the issues related to the operator sleep deficiency, its effects and the resulting risk. The issue is discussed on the example of a pilot, as a position in which the probability of occurrence of the phenomenon is high, with consequences of its occurrence that can be very severe. Despite the fact, the authors try to present the issues in a universal way enabling reference to a wide spectrum of different types of operators. In the article, concepts such as risk and fatigue are characterized. Furthermore, short and long-term fatigue are discussed, as well as the impact of shift work on human health and reliability. The second part presents methods of fatigue monitoring useful in aviation. The summary emphasizes the need for a holistic approach to the issue of crew fatigue in the management and the need for actions before commencing with work.

Essential self-adjointness of real principal type operators

We study the essential self-adjointness for real principal type differential operators. Unlike the elliptic case, we need geometric conditions even for operators on the Euclidean space with asymptotically constant coefficients, and we prove the essential self-adjointness under the null non-trapping condition.

New concepts of inverse fuzzy mixed graphs and its application.

Fuzzy mixed graph (FMG) can be used to model some graphical intercommunication network systems if there are many directed and undirected relations between some vertices. In inverse fuzzy graph, the membership value of edges are greater than or equal to the minimum of the membership value of the corresponding vertices. In inverse fuzzy mixed graph (IFMG), directed and undirected relations exist between some vertices and it can be used to analyze many graphical problems of real life such that the membership values of edges are greater than or equal to the minimum of the membership value of the corresponding pair of vertices. In this article, the concept of IFMG is introduced first with some of its properties. Then some isomorphic properties are studied and complement of IFMG is given. Different types of operations like union, intersection, product and join between two IFMGs are defined and investigated some of their related results. An algorithm of the proposed method is executed to identify some vertices. An application is depicted using the concept IFMG to examine the order of vertices in a social network group according to communication gaps.

CIBERSECURITY ON INTERNET OF ROBOTICS THINGS: EXPERIMENTAL PLATFORM

The Internet of Robotic Things (IoRT) is a technology that looks for monitoring, operating, and maintaining the tasks of multiple robots through the cloud. However, using these robots in cyberspace has a risk and an inherent problem in cybersecurity. To analyze the implications of this technology, the objective was to design, operate and submit an IoRT system with the default configuration. The proposed methodology consisted of designing an IoRT architecture; implement three robotic platforms linked to the cloud, applying a sniffing and spoofing cyberattacks, assess the impacts, and propose solutions. The experiment used three prototypes: two servo motors, a 6-degree-of-freedom arm, and a workstation with a robot. Additionally, the tools of the experiment were a conventional computer, a Raspberry Pi microcomputer, the Robotic Operative System middleware, the Kali Linux distribution, and the ThingSpeak cloud service. The contributions of the work were three, first it was proven that four types of links are sufficient to homologate, and ensure the integrity, reliability, and availability in the operation of different types of robots. Also, it was possible the connection of these robots even though they are not designed to work on the internet through a slave-robot node link. Finally, a real list of the consequences was obtained, given the vulnerabilities and the attacks tested, as well as some recommendations.Keywords: Cybersecurity, IoRT, Industry 4.0., Common Vulnerabilities and Exposures, Cloud, ROS.

Schatten-von Neumann classes of integral operators

In this work we establish sharp kernel conditions ensuring that the corresponding integral operators belong to Schatten-von Neumann classes. The conditions are given in terms of the spectral properties of operators acting on the kernel. As applications we establish several criteria in terms of different types of differential operators and their spectral asymptotics in different settings: compact manifolds, operators on lattices, domains in Rn of finite measure, and conditions for operators on Rn given in terms of anharmonic oscillators. We also give examples in the settings of compact sub-Riemannian manifolds, contact manifolds, strictly pseudo-convex CR manifolds, and (sub-)Laplacians on compact Lie groups.

Bipolar Picture Fuzzy Graphs with Application

In this manuscript, we introduce and discuss the term bipolar picture fuzzy graphs along with some of its fundamental characteristics and applications. We also initiate the concepts of complete bipolar picture fuzzy graphs and strong bipolar picture fuzzy graphs. Firstly, we apply different types of operations to bipolar picture fuzzy graphs and then we introduce various products of bipolar picture fuzzy graphs. Several other terms such as order and size, path, neighbourhood degrees, busy values of vertices and edges of bipolar picture fuzzy graphs are also discussed. These terminologies also lay the foundations for the discussion about the regular bipolar picture fuzzy graphs. Moreover, we also discuss isomorphisms, weak and co-weak isomorphisms and automorphisms of bipolar picture fuzzy graphs. Finally, at the base of bipolar picture fuzzy graph we present the construction of a bipolar picture fuzzy acquaintanceship graph, which would be an important tool to measure the symmetry or asymmetry of acquaintanceship levels of social networks, computer networks etc.